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Mark W Rogers
 

Mark W Rogers Ph.D., P.T.

Academic Title: Professor
Primary Appointment: Physical Therapy and Rehabilitation Science
Secondary Appointments: Anatomy and Neurobiology, Neurology
Administrative Title: Interim Chair
mrogers@som.umaryland.edu
Location: Allied Heath Building, 100 Penn Street, 205D
Phone: (410) 706-0841

Personal History:

Dr. Rogers graduated from the University of Connecticut, Storrs in 1973 with a B. S. in Physical Therapy. From 1972-1980 he practiced clinical physical therapy in rehabilitation and acute care medical centers and in extended care and home health settings. From 1975-1977, he completed his M.S. degree in Exercise Science focused on motor learning and behavior at the University of Massachusetts, Amherst. His doctoral studies in Neuromuscular Therapeutics were performed in the Department of Physical Therapy, Carver School of Medicine, at the University of Iowa, Iowa City, where he received his Ph.D. in 1985. From 1984-1986, he was Predoctoral & Postdoctoral Fellow in rehabilitation and neurophysiology at McGill University, School of Medicine, Montréal, Canada. In 1986, he joined the Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, at Northwestern University, Chicago, Illinois, as Contract Faculty and then Assistant Professor in 1987. He was promoted to Associate Professor with tenure in 1993. He remained at Northwestern until 2008 when he joined the Department of Physical Therapy and Rehabilitation Science at the University of Maryland, Baltimore, and School of Medicine as a tenured Professor. Dr. Rogers is also Vice Chair for Research; Director, PhD Program in Physical Rehabilitation Science (PRS); Director, National Institute for Disability Rehabilitation Research (NIDRR), University of Maryland Advanced Neuromotor Rehabilitation Research Training (UMANRRT) Program; and Co-Director, Mobility Function & Neuroplasticity Core, Claude D. Pepper University of Maryland Older Amerocans Independence Center (UMOAIC).


Research Interests:

The Human Balance and Movement Rehabilitation Laboratory studies the interaction of neuromotor, biomechanical, and behavioral processes that control human balance and movement and their disorders in aging and adults with chronic functional limitations due to central nervous system (CNS) damage such as Parkinson’s disease and stroke. The studies are directed at understanding the pathological changes in motor control that disrupt whole-body actions during standing, walking, and reaching in order to develop mechanistically based rehabilitation interventions for restoring functional independence.

A main focus is on how protective movements of the limbs such as stepping and reaching are controlled in order to stabilize balance. Further interests are in determining how predictive and reactive neural control processes are shaped and adapted by preparatory motor states and sensory information accompanying movements and from the environment in interaction with the biomechanical factors and behavioral contexts that impact motor control. A related theme is focused on understanding how posture and locomotion actions are coupled within the CNS in order to develop novel therapeutic interventions for enhancing posture and locomotion coupling and improving physical mobility.

Current projects investigating these themes are:

Protective Stepping and Falls in Aging: We have been investigating the neuromechanical bases of why protective reflex stepping for balance recovery is altered with aging as a risk factor for falls. We observed that successfully stepping sideways as a protective response to imbalance is problematic for many older individuals as characterized by the frequent use of multiple, short, recovery steps with inter-limb collisions when attempting to secure lateral balance. These changes in stepping patterns may result from impairment in hip joint torques and the combined deficits discriminate prospectively between fallers and non-fallers. Currently, we are determining the balance tolerance limit to effective lateral balance recovery among older adults at risk for falls and assessing whether this balance disturbance “break point” is directly linked with limitations in hip muscle performance and underlying changes in muscle composition as determined by computerized tomography (CT). This project is supported by an RO1 grant (Rogers) and a P30 Claude D. Pepper, Older Adults Independence Center grant (Goldberg) from the National Institute on Aging.

Intervention to Enhance Lateral Balance Function and Prevent Falls in Aging: We have begun a clinical trial to determine whether a combined intervention of induced lateral step training and hip muscle strengthening is more effective than either intervention alone or a standard minimal-intensity exercises program (control). Inducing repetitive, high force, high speed use of the hip muscles to control lateral balance progressively challenges these key postural muscles during protective balance reactions that are critical to preventing falls. The inclusion of progressive resistance training allows us to compare the effectiveness of high intensity balance training with isolated muscle and joint training and their combined effects on prospective fall frequency determined during a 1-year follow-up period post-training. This project is supported by an RO1 grant from the National Institute on Aging.

Posture and Locomotion Coupling in Parkinson’s Disease: We are investigating whether abnormal spatiotemporal coupling between anticipatory postural adjustments (APAs) that normally precede the initiation of walking is linked with start hesitation and freezing of gait in patients with Parkinson’s disease. We found that robotic assistance with lateral weight transfer APAs concomitant with subjects’ effort to begin stepping, acutely improves kinetic and kinematic properties of the APA and stepping. Repeated exposures to robotic limb loading or ground surface vibration enhancement of stepping during semiweekly training over 6 weeks resulted in sustained effects post-training. This suggested that impaired coupling of posture and locomotion may contribute to neuromotor timing deficits related to start hesitation of walking. The intervention approach is being extended to other posture and locomotion coupling tasks involving gaze shifts while turning in stepping, sit-to-stand, standing reach, and ongoing walking. This project is supported by an R21 grant from the National Institute of Child Health and Human Development/National Center for Medical Rehabilitation Research.

Lab Techniques and Equipment:

Our studies are performed using neurophysiological and biomechanical techniques. Three-dimensional kinematic information is obtained using one of two motion capture systems: 1. For tasks involving gait or other types of translational movement, a six-camera Vicon system can passively determine the spatial position of multiple body markers with a resolution of less than a few millimeters; and 2. For stationary tasks or measurements requiring sub-millimeter resolution, a four sensor Optotrak system is used to determine the spatial position of up to 512 active infrared body markers. Ground reaction force data is obtained from either dual AMTI force platforms or a single Bertec force platform. Electromyographic activity for up to 24 muscles is measured using a Noraxon 24-Channel wireless EMG system, and visual gaze data can be collected with an EyeLink II head-mounted, binocular system from SR Research. Visual stimuli are presented on a 7 ½’ x 10’ Da-Lite rear projection screen by a BenQ SP890 high resolution/brightness digital projector. Peripheral nerve and muscle stimulation are applied with a Grass S88 dual output square pulse stimulator. Non-invasive brain stimulation methods include transcranial direct current (tDCS) and pulsed current stimulation (tPCS), transcranial magnetic stimulation (TMS) delivered using a Magstim 200 stimulator with Brainsight 2 Neuronavigation System, and acoustic startle stimuli. Data collection systems are coordinated and synchronized by a Motion Monitor Model 2000 data collection/processing system, which provides immediate display of all experimental data in graphical/tabular form and/or as animations. Balance and gait perturbations are applied using a customized closed-loop stepper motor waist-pull system and an ActiveStep GS treadmill by Simbex. Spatiotemporal gait patterns are recorded using a GAITRite Portable Walkway System. Isokinetic joint torque measurements are obtained with a Biodex System 4 Pro Dynamometer.


Laboratory Personnel:

Collaborators:
Jay Barton, PhD, Assistant Professor, Internal models & balanced reaching after stroke
Brock A. Beamer, MD, Assistant Professor, Gerontology, geriatric medicine, exercise and falls
Rob Creath, PhD, Assistant Professor, Sensorimotor control of posture & gait in Parkinson’s disease
Michelle Prettyman, DPT, Assistant Professor, Research Coordinator, neurotherapeutics
Douglas Savin, PT, PhD, Assistant Professor, Neuromotor adaptation & rehabilitation of gait & balance in stroke & aging
Sandy McCombe Waller, PT, PhD, NCS, Associate Professor, Neuromotor recovery & rehabilitation of arm function after stroke

Ph.D. Students in Physical Rehabilitation Science:
Mario Inacio, MS, Neuromuscular control & balance rehabilitation in aging
Judith Morgia, BS, Fatigue effects on proprioception & balance rehabilitation in aging

Postdoctoral Fellows:
Woei-Nan Bair, MS, PhD, Physical therapy, sensorimotor control of posture across the lifespan
Valentina Graci, PhD, Vision and mobility, cognition, balance rehabilitation
Patricia Young, PhD, Dynamic stability of walking in aging, balance asymmetries, falls rehabilitation

Research Staff:
Janice Abarro, BS
Andrea Gaeta, BS
Toye Jenkins, MPT
Kaitlin Riddle, MS

Links of Interest:

Publications